The German Army called it the Salatschüssel (salad bowl). "The Brodie helmet"

The Brodie helmet is a steel combat helmet designed and patented in 1915 by Englishman John Leopold Brodie. In modified form it became the Helmet, steel, Mark I in Britain and the M1917 Helmet in the U.S. Colloquially, it was called the shrapnel helmet, Tommy helmet, Tin Hat, and in the United States the doughboy helmet. Worn by Australians during WW2 and sometimes known as 'Panic Hat'. It was also known as the dishpan hat, tin pan hat, washbasin, battle bowler (when worn by officers), and Kelly helmet. The US version, the M1917, was copied from the British Mk 1 steel helmet of 1916. The German Army called it the Salatschüssel (salad bowl).